This research continues the investigation of the Navajo Ethno- medical Domain started by Werner. It is based on the insight that dealing with cultural knowledge in an 'exotic" language like Navajo it is unrealistic to ask Anglo anthropologists to make significant and very accurate contributions in the Navajo Language. Solid substantive work can ultimately be made only by native speakers who are in full control of the subtleties of their language. Therefore a cooperative arrangement is proposed between Northwestern University and the Navajo Health Authority (established by the Navajo Tribe in 1972 in response to a report by a Health Manpower Education Committee formed by HEW Secretary Elliot Richardson). It has been charged with planning and coordination of Health Education and Health Delivery by combining the best of Navajo Healing Sciences with the best of Anglo Medicine. In order to codify the native Navajo medical knowledge two parallel organizations are proposed: A Navajo (German et. al.) for substantive contributions in Navajo, and an Anglo (Werver et al.) which is concerned with the principles of medical encyclopaedia-making and the theory of cultutal knowledge (ethnoscience). This joint effort will result in The Medical Encyclopaedia of the Navajo. It will be gathered by ethnoscience techniques, analyzed and organized according to ethnoscience theory, published according to a systematic adaptation of ethnoscience principles to practical presentation, i.e., readability, and used for the education of Native American Physicians and paramedical personnel. This project will also contribute to better medical communication (Translation & interpretation) and therefore health care and medical management of the Navajo People -- ultimately to people anywhere who do not speak English.